10-Midterm

Question 1

1-Carious Lesion Detection
2-Carious Lesion Assessment
3-Caries Disease Diagnosis

Answer 1

1-recognition of changes in enamel/dentin/cementum that are consistent w/ having been caused by caries process

2-severity/extent—evaulation of characteristics of caries lesion once its been detected. Characteristics= optical, physical, chemical, or bio, color, size

3-caries disease diagnosis= professional summation of all signs/symptoms of disease to arrive at ID

Question 2

1-Lesion Detection Assessment
2- Diagnostic Tests

Answer 2

1-establish level of destruction present, aid in caries diagnosis, determine treatment decisions
2- Valid-test measures what is intended to measure= white spot lesion
Reliability- test can be repeated w/ same result—same lesion

Question 3

1- true +
2- false +
3- true -
4- false -

Answer 3

1-caries= present and test identifies it
2- diagnostic test incorrectly IDs when caries is absent
3- test correctly identifies individual as caries free
4-has caries & test incorrectly= caries free

Question 4

1-Sensitivity
2-Specificity

Answer 4

1-proportion of true positive that are correctly identified
2-proportion of true negatives that are correctly identified

Question 5

Detection Methods—Ideal Method

Answer 5

• reproducible, accurate
• easy to use/learn
• useful on surfaces
• influence on treatment

Question 6

Visual Examination of Caries

Answer 6

• widely used, quick, cheap, easy
• dry, clean tooth w/ good light, and mirror
• all surfaces
• occlusal, smooth surface (proximal), root caries
• dichotomous decisions—presence / absence
• Can’t see interproximal so it is absent upon examination

Question 7

Explorer

Answer 7

• explorer can break off part of the tooth because it is fragily
• –doesnt add anything to detection yield
• use it to feel margins/defects
• clean debris from fissures/interproximal spaces and confirm/assess cavitations
• hardness of root/dentin
• texture of white spot

Question 8

Occlusal Surfaces

Answer 8

-low sensitivity= 0.30 and high spec.

Question 9

ICDAS

Answer 9

0- sound surface
1-first visual change in enamel
2-distinct visual change in enamel
3-localized enamel breakdown bc of caries w/ no visible dentin
4-non cavitated surface w/ underlying dark shadow from dentin
5-distinct cavity w/ visible dentin
6-extensive distinct cavity w/ visible dentin

Question 10

Interproximal Detection

Answer 10

• visual inspection via bitewing radiographs
• but doesnt detect early subsurface demineralization or lesion activity

Question 11

Caries—

Answer 11

1. Biofilm
2. Pellicle
3. Enamel
4. Dentin

Question 12

1-E Classification
2-D1 Classification
3- D2 Classification

Answer 12

1-lesion penetrates through part of the enamel
-radiolucent triangle w/ base at enamel and point to DEJ
2-lesion penetrates into dentin but is less than 1/2 through dentin toward pulp…radiolucent triangular lesion in enamel
3- lesion extends= more than 1/2 but less toward pulp, deeeeep appearance

Question 13

1-Transillumination
2-DIAGNOdent

Answer 13

1-intense beam of white light, tip on facial surface, caries has lower index of transmitted light, detection of proximal lesions, inexpensive (light through tooth)
2-detection of early occlusal lesions, fluorescence from lesion=produced from bacterial porphyrins, tip on tooth, normal enamel exhibits, intensity=size…drawbacks= heavely stained fissues and false positives

Question 14

Caries Disclosers

Answer 14

• colored dye stains organix matrix of less mineralized dentin
• drawback= over prep of pulp exposure due to natural differences in colalgen content in diff parts of dentin

Question 15

Active Lesion

Answer 15

• chalky opaque, white dull
• rought/soft
• plaque stagnation–covered by plaque
• close to gingiva
• high surface porosity

Question 16

Inactive Lesions

Answer 16

• translucent/white-brown
• shiny surface
• smooth/hard
• non-plaque stagnation
• away from gingiva
• low surface porosity

Question 17

Answer 17

Active Lesion

Question 18

Answer 18

Inactive White Spot Lesion—–reversible & stable

Question 19

Differential Diagnosis

Answer 19

—loss of tooth structure

• Erosion
• Attrition
• Abrasion
• —white spot differential
• hypoplasia
• fluorosis

Question 20

Answer 20

Decalcification

Question 21

Answer 21

Fluorosis

Question 22

1- alginate
2-gypsum
3- Dental impression media

Answer 22

1-impression making
2-dental casts
3- used to reproduce accurate replicas of intraoral and extraoral tissues

Question 23

Impression Making Goals

Answer 23

1-obtain accurate negative images, all anatomic details from patients
2-transform images into positive physical or virtual casts= diagnostic, planning, and treatment

Question 24

Digital Impression Media

Answer 24

• iTero (cadent)
• E4D (D4D)
• Lava (3M ESPE)
• —-we use—-CAD—CEREC (sirona)

-digitally imaged impressions to create virtual casts on restorations may be fabricated

Question 25

Physical Media

Answer 25

1- rigid impression---**compounds**, impression plaster, zinc oxide 2-flexible impression---agar hydrocolloids (reversible), elastomeric, alginate hydrocolloids(irreversible)

Question 26

Dental Alginate Impression

Answer 26

-hydrocolloid consisting of a sol of alginic acid having a physical state that is changed by irreversible chemical reaction forming insoluble Ca alginate

Question 27

Colloids are dual phase

Answer 27

- internal (dispersed) phase contained w/in matrix (dispersion) phase - dispersed consists of molecules held together by primary/secondary attraction forces w/in matrix (dispersion)

Question 28

Solid Colloids

Answer 28

-dispersed (internal) phase particles are concentrated enough to form a semi-solid material=gel

Question 29

Alginate Impression Material

Answer 29

- dispersed phase consists of chains of Ca alginate (micelles) w/in dispersion phase of H2O - powder(K alginate) and water creates colloidal solution (for setting reaction)

Question 30

**Alginate Impression Material: 1-**Potassium Alginate 2- Calcium sulfate

Answer 30

1- source of soluble aginate 2- initiates reaction ---Ca ions reacts w/ the K Alginate sol to create the gel of Ca alginate

Question 31

1) Sodium Phosphate 2) Filler Particles

Answer 31

1) -slows down reaction of Alginate Impression - it reacts with Ca, delaying the setting reaction 2) strengthens the set gel (zn oxide)

Question 32

Valuable Properties of Alginate Impression

Answer 32

- good elasticity---removed easily - good elastic memory - easy to use - sets quickly - good accuracy - inexpensive ---restorations, ortho, peds, oral surgery

Question 33

Invaluable Alginate Impression

Answer 33

- good but not great accuracy, cant reproduce fine details, not recommended for fix restorations - elastic memory doesnt remain stable over time - water makes up dispersion phase that **evaporates** over time---shrinks and distorts impression - water will form exudate(ooze) on to surface of alginate impression: **syneresis** - if soaked in H20 it will absorb it and distort anyway via **imbibition**

Question 34

Dental Casts

Answer 34

- electroplated casts - epoxy resin - digital

Question 35

Gypsum Casts over the other Casts

Answer 35

- easy - compatible w/ physical impression materials - inexpensive

Question 36

Gypsum

Answer 36

- grinding, heating, and pressure - drives off portion of H20 found in gypsum converting it from **dihydrate** to **hemihydrate**= **calcining** - --summary---gypsum= heating dihydrate

Question 37

1- a- hemihydrate 2-b-hemihydrate

Answer 37

1-die stone or improved stone---calcining process results in gypsum particles that are small, smooth, and dense (microstone) 2-dental plaster---calcining process results in gypsum particles that are large, porous, and irregular (mounting stone) ---both are chemically the same, but the makeup of these particles= diff dental casts

Question 38

Making Dental Casts

Answer 38

- Added H20 causes dissolution of CaSO4 hemihydrate creating a saturated solution of CaSO4 - no longer calcining - will eventually be followed be precipitation of CaSO4 dehydrate crystals w/ heat generation (exo) equivalent to heat used to original calcining process of gypsum - crystalization= expansion - continues until no more CaSO4 dehydrate can precip= cast - but H20 leaves voids and that reduces the strength of cast

Question 39

1-a hemihydrate 2-b hemihydrate

Answer 39

1-require less H20 as part of setting so the cast=harder and more resistant to fracture/abrasion 2-require more H2O as part of setting so casts= softer and more easily abraded/fractured ---altering amt of H20 added to powder, alters expansion of gypsum(not good idea)